12.51 - detector bias and leakage currents - detector 3 has no current
- other detectors ok
13.13 - tried changing from HV3 cables to HV4 - still open circuit
- tried different permutations of moving HV-4 braid and core cables (high voltage to ground connections)
(dssd3)
(all directions defined as if looking upstream)
- core -> bottom, braid -> left open - circuit
- core -> top, braid -> right trips at 8V
- core -> bottom, braid -> right open - circuit
- core -> top, braid-> left trips at 8V
- removed jumpers - still trips
13.36 - testing continuity of bond wires on dsssd 3208-14 & 3208-15
- observe 20 ohm resistance on p+p and p+n bond wires
19:41 - dsssd 1 and 2 not biasing, 3 ok.
- changed bias configuration -> HV core 1 & 2 now on top, braid on right
- ribbon cables for DSSSD #1 & #2 p+n junction strips down were misaligned
- all detectors biased succesfully
HV cable configuration (looking upstream): HV-1 Core -> top-inner (FEE 1)
HV-2 Core -> top-middle (FEE 5)
HV-3 Core -> bottom-outer (FEE 11)
HV-1 Braid -> right-inner (FEE 2)
HV-2 Braid -> right-middle (FEE 6)
HV-3 Braid -> left-outer (FEE 12)
Attachment 3 - rough sketch of HV cable configuration, looking upstream.
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